Gaseous signal molecule SO2 regulates autophagy through PI3K/AKT pathway inhibits cardiomyocyte apoptosis and improves myocardial fibrosis in rats with type II diabetes
Junxiong Zhao1,2,#, Qian Wu3,#, Ting Yang1,4,#, Liangui Nie2, Shengquan Liu2, Jia Zhou5, Jian Chen6, Zhentao Jiang7, Ting Xiao8,*, Jun Yang2,*, and Chun Chu1,*
1Department of Pharmacy, The Second Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang 421000, 2Department of Cardiology, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang 421000, 3Department of General Practice, The Second Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang 421000, 4School of Pharmaceutical Science of University of South China, Hengyang 421000, 5Department of Ultrasound Medicine, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang 421000, 6Department of Critical Care Medicine, The Affiliated Nanhua Hospital, Hengyang Medical School, University of South China, Hengyang 421000, 7Department of Cardiology, The Affiliated Nanhua Hospital, Hengyang Medical School, University of South China, Hengyang 421000, 8Department of Cardiology, Shenzhen Longhua District Central Hospital, Longhua Central Hospital Affiliated Guang-dong Medical University, Shenzhen 518000, China
Author contributions: J.Z. and Q.W. were responsible for the execution of the experiments and the writing of the manuscript. T.Y., L.N., S.L., and J.Z. participated in molecular biology testing and experimental design, J.C. and Z.J. were responsible for the execution of experiments and data analysis. T.X., J.Y., and C.C. were responsible for the design of the experiment. All authors contributed to this work and approved the submitted version.
Received: July 29, 2022; Revised: September 8, 2022; Accepted: September 13, 2022
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Myocardial fibrosis is a key link in the occurrence and development of diabetic cardiomyopathy. Its etiology is complex, and the effect of drugs is not good. Cardiomyocyte apoptosis is an important cause of myocardial fibrosis. The purpose of this study was to investigate the effect of gaseous signal molecule sulfur dioxide (SO2) on diabetic myocardial fibrosis and its internal regulatory mechanism. Masson and TUNEL staining, Western-blot, transmission electron microscopy, RT-qPCR, immunofluorescence staining, and flow cytometry were used in the study, and the interstitial collagen deposition, autophagy, apoptosis, and changes in phosphatidylinositol 3-kinase (PI3K)/AKT pathways were evaluated from in vivo and in vitro experiments. The results showed that diabetic myocardial fibrosis was accompanied by cardiomyocyte apoptosis and down-regulation of endogenous SO2-producing enzyme aspartate aminotransferase (AAT)1/2. However, exogenous SO2 donors could up-regulate AAT1/2, reduce apoptosis of cardiomyocytes induced by diabetic rats or high glucose, inhibit phosphorylation of PI3K/AKT protein, up-regulate autophagy, and reduce interstitial collagen deposition. In conclusion, the results of this study suggest that the gaseous signal molecule SO2 can inhibit the PI3K/AKT pathway to promote cytoprotective autophagy and inhibit cardiomyocyte apoptosis to improve myocardial fibrosis in diabetic rats. The results of this study are expected to provide new targets and intervention strategies for the prevention and treatment of diabetic cardiomyopathy.